I am designing a notch filter used for doing some emissions testing, used to notch out the fundamental from a transmitter antenna. However, i was told I need to spec the components to be able to handle the electrical stress at resonance.

My first thought was, well if it is at resonance, then the only stress would be due to the power dissipated due to the series resistance, but that is in the order of milli-ohms for the inductors, so it is insignificant.

Any thoughts on this?

The filter is a 3 pole T-type filter, with two series parallel-resonant ckts and a shunt series resonant circuit.

There are other considerations, though resistance is the one that generates heat.

Here's some math you want to try sometime, take a series resonant circuit being feed with its resonant frequency, and calculate the voltage drop across the coil and the cap. It can be quite impressive.